Section A
47. 系統解析：So many people use the cell phone frequently every day. But (47) surprisinglylittle is certain about the health effects of its use. Manufactures (48) maintain that cell phones meet government standards for safe radio-frequency radiation emission,but enough studies are beginning to document a possible (49)increase in rare brain tumors ( 腫瘤), headaches and behavioral disorders in children to cause concern. So far, the evidenceisn't (50) conclusive_ on whether the use of cell phones (51)contributes to any increased risk of cancer. In a new trial, researchers asked 47 volunteers to (52) participate in a project to measure glucose (葡萄糖 ) consumption in the brain by scanning the brain to see how cells use energy. For both 50-minutescans, the volunteers had a cell phone (53) fixed to each ear.During the first scan, the devices were turned off, but for the second scan, the phone on the right ear was (54) switched on and received a recorded-message call, although the volume was muted (消音 ) so the noise wouldn't bias the results. The results of the second scan showed that the (55) region of the brain nearest to the device had higher rates of glucose consumption than the rest of the brain. The study shows that cell phones can change brain activity, and (56) provides a whole new avenue for scientific inquiry, though it doesn't say anything about whether cell-phone radiation can cause cancer.
【譯文】

N。此空需填一個副詞。選項中有兩個副詞，immensely表示“極大的”，surprisingly表示“令人驚訝的”，該句意為：但——，幾乎沒有人清楚使用手機在健康方面的影響。故選N。
48. 系統解析：H。此空需填一個原形動詞。句意為，制造商——手機符合政府安全射頻輻射釋放標準。maintain“堅持(認為)，堅稱”符合此處語境，故選H。derive“源于，得自”，increase“增加，增長”，participate“參與，參加”。

49. 系統解析：G。此空需填一個單數名詞。mission“使命，任務”，不符合語境。increase“增加，增長”符合句意，且后文中緊接著提到increased一詞，故選G。

50. 系統解析：A。此空需填一個形容詞修飾限定evidence。conclusive“令人信服的，確鑿的”，符合句意，故選A。該句意為：到目前為止，對于使用手機是否導致癌癥的風險增加，證據并不確鑿。

51. 系統解析：B。此空需填一個動詞的單數三人稱形式。contribute t0為固定搭配，意思是“促成……，導致……”，故選B。

52. 系統解析：J。此空需填一個原形動詞，表朗“志愿者”和“項目”之間的關系，且須能與介詞in搭配使用。Participate in為固定搭配，意思是“參加，參與(某活動)”。故選J。

53. 系統解析：E。此空需填一個動詞的過去分詞。switched“轉換”，不符合此處語境。fixed“固定”，符合句意，故選E。該句意為：志愿者的每一只耳朵上都固定了一部手機。

54. 系統解析：O。此空需填一個動詞的過去分詞表示被動。所剩選項中符合條件的只有O項。switch on表示“打開，開啟”，故選O。

55. 系統解析：M。此空需填一個名詞。第二次的掃描結果顯示，靠近手機的大腦_______比大腦其他_______的葡萄糖消耗率要高。很明顯，只有regions符合句意。故選M。

56. 系統解析：L。此空需填一個動詞的單數三人稱形式。所剩選項中只有L項符合。provides“提供”，用在此處符合句意，故選L。該句意為：研究還為科學探究提供了一種全新的途徑，但是它對手機輻射是否會引發癌癥并未作任何說明。

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